This episode's headline: After New Hampshire; Gene Therapy; Paying for Child Care; Reading the Results. ANCHOR: JIM LEHRER; GUESTS: SEN. JOHN McCAIN; PAUL GIGOT, Wall Street Journal; MARK SHIELDS, Syndicated Columnist; CORRESPONDENTS: TERENCE SMITH; BETTY ANN BOWSER; RAY SUAREZ; MARGARET WARNER; PAUL SOLMAN; TOM BEARDEN; GWEN IFILL; TERENCE SMITH; KWAME HOLMAN; SPENCER MICHELS